Ballarat's SES received just three calls for assistance during the evening, despite almost 20mm falling in the space of just over an hour from 12.40am to 2am.

Among the calls were to fix leaky roofs in Frances Crescent, Ballarat East and at Gillies Street Wendouree.

But it was a different story in nearby regions for many residents with Hepburn crews called out eight times for a series of trees down and building damaged.

Trees were brought down in Blampied, Bald Hills and Blackwood among others.

The Ararat branch answered nine requests, but the worst in the mid-western region was Stawell with 22 requests for help in just over an hour.

Stawell in fact has received 68.4mm in the past 24 hours, with the majority of that (46mm) falling between 8.40pm and 10pm.

However, the biggest damage across the state centered at Lake Purrumbete near Colac where a caravan park saw more than 20 vans damaged and a number of trees brought down.

The other area across the state which was most hurt was Rosebud on the Mornington Peninsula.

An SES spokesperson said the emergency authority responded to 125 call out across Victoria, with expectation of more flash flooding across the north and north-eastern parts of the state today and the storm system moves through.

Ballarat has officially received 18.6mm of rain in the past 24 hours, on top of the 8.4 recorded the previous day. This means nearly an inch has fallen this month despite May being just two days old.

It is already more this month than any of the completed previous four this year.

If you have experienced any issues overnight and need assistance, you can contact the SES on 132 500 or log onto ses.vic.gov.au

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